Catheter

Abstract

Provided is a catheter that is manufacturable in a simplified fashion. The catheter 1 includes: a catheter tube 11 including a tip-flexible part 11A that has an inner tube (first tube 61) and a plurality of divided tube members 620 to 625 that are disposed on outer circumference of the inner tube and independent of each other; one or a plurality of metal rings disposed in the tip-flexible part 11A; one or a plurality of temperature sensors disposed corresponding to the one or the plurality of metal rings; and a handle 12 attached at a base end of the catheter tube 11. A rate of a thickness of the metal ring to an outer diameter of the metal ring is 7.5% or greater. The metal ring and the plurality of divided tube members 621 to 625 are both so disposed in the tip-flexible part 11A as to be fitted on an outer circumferential surface of the inner tube side by side in an axial direction of the catheter tube 11.

Description

TECHNICAL FIELD[0001]The invention relates to a catheter having a temperature sensor.BACKGROUND ART[0002]An operation that performs cauterization or “ablation” with use of an ablation catheter has been performed as one of medical treatments for arrhythmia, etc. Such ablation that uses the ablation catheter may be performed on a site that involves the arrhythmia inside the heart, for example. In general, methods of the ablation may be roughly classified into a method that performs heating and a method that performs cooling. More specifically, the methods of the ablation may be roughly classified into a high-temperature ablation that uses a high frequency current and a low-temperature ablation that uses liquid nitrous oxide, liquid nitrogen, etc. When performing the ablation of a site such as the posterior wall of the left atrium of the heart by means of the ablation catheter, i.e., upon surgical ablation of the left atrium, the esophagus located in the vicinity of the posterior wall ...

AI Technical Summary

Benefits of technology

[0010]In the catheter according to the invention, the metal ring has the thick structure. In other words, the rate is 7.5% or greater. Thus, a rate at which heat having transferred to the metal ring dissipates to the surrounding tissues becomes smaller than a metal ring having a thin structure. Hence, upon measuring an internal temperature of, for example, a hollow organ inside the body, such as the esophagus, by means of the temperature sensor, the internal temperature of the hollow organ having been subjected to heating or cooling is transmitted accurately to the temperature sensor. As a result, an accuracy of measurement upon measuring the internal temperature increases as compared with the metal ring having the thin structure. However, upon forming the tip-flexible part of the catheter tube, such a thick-structured metal ring may involve difficulties in employing an example method that causes the metal ring to be embedded into the outer circumferential surface of a second tube by striking the metal ring from outside. To address this, in the catheter according to the invention, the one or the plurality of metal rings each provided corresponding to the temperature sensor and the plurality of divided tube members that are independent of each other are both so disposed in the tip-flexible part as to be fitted on the outer circumferential surface of the inner tube side by side in the axial direction of the catheter tube. This makes it easier to form the tip-flexible part even when the metal ring is made thick as described above.

[0011]In the catheter according to the invention, desirably, the inner tube may have an opening that is formed in the axial direction from a tip end of the inner tube and allows the metal ring and the temperature sensor to be electrically coupled to each other. This facilitates the electrical coupling of the metal ring and the temperature sensor, making it easier to so dispose the metal ring as to be fitted on the outer circumferential surface of the inner tube. This also facilitates the formation of the opening on the inner tube, making it even easier to form the tip-flexible part.

[0012]In the catheter according to the invention, desirably, the metal ring and the plur

Problems solved by technology

However, upon forming the tip-flexible part of the catheter tube, such a thick-structured metal ring may involve difficulties in employing an examp

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